Method and apparatus for shearing rolled metal blanks

ABSTRACT

An improved method and apparatus for shearing hot rolled metal blanks in which shear blades having a particular shape are used to shear the metal blank to produce a tapering transverse edge configuration having a longitudinally extending control portion relative to the top and bottom surfaces of the blank thereby to minimize laminating of the sides in subsequent rolling operations.

inventor John Gross Salem, Ohio Appl. No. 871,992

Filed Sept. 25, 1969 Division of Ser. No. 665,816, Sept. 6, 1967, Bat eilflefl Patented Feb. 23, 1971 Assignee Gulf 8: Western Industrial Products Company Grand Rapids, Mich.

METHOD AND APPARATUS FOR SHEARING ROLLED METAL BLANKS 4 Claims, 12 Drawing Figs.

U.S. Cl 225/103, 83/923, 72/324 Int. Cl B261 3/00 Field of Search 72/203, 204, 129, 324; 225/93; 83/51, 623, 694; 225/4, 91, 103

DIRECTION OF R0 LLl N G [56] References Cited UNITED STATES PATENTS 1,366,063 1/1921 Culhane, Jr. 83/51X 1,525,456 2/ 1925 Luetscher et al. 72/203 2,057,928 10/1936 Stahl 83/51 2,061,659 11/1936 Iversen 72/203 3,032,337 5/1962 Holman 83/51X 3,416,347 12/1968 Walsh et a1. 83/51 Primary Examiner-Milton S. Mehr Attorney-Meyer, Tilberry and Body ABSTRACT: An improved method and apparatus for shearing hot rolled metal blanks in which shear blades having a particular shape are used to shear the metal blank to produce a tapering transverse edge configuration having a longitudinally extending control portion relative to the top and bottom surfaces of the blank thereby to minimize laminating of the sides in subsequent rolling operations.

I PATENTEDFEBZBIQYI 3565.309

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DIREC N OF ROLL! 32 INVENT JOHN GRO ATTORNEYS PATENTEU FEB23 I97! sum 2 BF 2 FIG. 2A 37 'FIGISA' 46 FIG 4A BMW FIG. 4B EIE'D' FIG. 5B CILID INVENTOR.

JOHN GROSS ATTORNEYS METHOD AND AIPFARATUS FOR SHEARING ROLLED METAL ELANKS This application is a divisional application of application Ser. No. 665,816, filed Sept. 6, 1967 now Pat. No. 3,492,853.

This invention relates to the art of rolling metal blanks and, more particularly, is directed to an improved method and apparatus for shearing rolled metal blanks during the rolling process.

The present invention is particularly adapted for reducing the effect of creep or uneven fiber elongation encountered in hot rolling of aluminum blanks into thin strips and it will be discussed with particular reference thereto; however, the in vention has broader applications and is applicable to any process in which metal is being reduced in cross section and lengthened through mechanical working.

Aluminum normally is cast in cakes or blanks up to approximately inches thick and these cakes are hot rolled to form strips by means of a reversing hot mill normally followed by several mill stands in tandem. The aluminum cakes, as case, usually have transverse end surfaces which are perpendicular to the top and bottom surfaces'of the cake. As the cake is passed through the rolling mill, the cake is progressively reduced in thickness in conventional manner. However, it normally occurs in the hot rolling of aluminum that the surfaces of the cake in engagement with the rolls tend to elongate more than the interior of the cake. In otherwords, the outer fibers of the cake elongate more than the inner fibers which produces a lapping or laminated effect at the ends of the resulting sheets. Moreover, with some-types of aluminum, these laminated portions tend to spread apart at their outer ends and this condition is known as alligatoring.

To eliminate the laminated sections as well as the alligator portion, the cakes of aluminum are sheared periodically. The prior art has conventionally sheared the cakes with shears which produce an end which is substantially the same as when the cake was first cast, that is, the transverse end of the sheared piece of aluminum is substantially perpendicular to the top and bottom surfaces of the cake. As further rolling of the aluminum occurs, additional laminating and alligatoring of the sheet occurs, thereby necessitating additional shearing of the cake.

The present invention contemplates minimizing the effects of uneven fiber elongation in a metal rolling operation by for uneven fiber elongation thereby minimizing the undesirable laminating and alligatoring. I

in accordance with the present invention, there is provided an improved method of rolling a 'metal blank which includes the step of shearing the blank to produce a tapered transverse edge configuration having a longitudinally extending central portion relative to the top and bottom surfaces of the blank with the remaining portion of the edge tapering rearwardly of the blank.

In accordance with another aspect of the invention, there is provided an improved shearing device for minimizing laminating and alligatoring of rolled metal blanks. The shearing device comprises two shearing blades mounted in opposed relationship to one another and means to reciprocate at least one of the blades thereby to shearthe metal blanks placed between the blades. Each blade has opposed shearing faces which define therebetween an included angle which is within the range of to 120.

It is a primary object of this invention to provide a method and apparatus for reducing the effects of laminating and alligatoring of metal blanks during a rolling operation.

A further object of this invention is to provide novel shearing apparatus which is operative to shear a metal blank in a manner which reduces the effects of laminating and alligatoring in subsequent rolling operations.

Another object of this invention is to provide a method of shearing a rolled metal blank which includes the step of shearing the metal blank to form a forwardly tapering transverse edge configuration.

shearing the blank to produce a configuration which provides 4 These and other objects and advantages will become more apparent from the following description when taken in connection with the accompanying drawings in which like reference numerals indicate like parts in the various views.

FIG. 1 illustrates in sequential steps A through F the laminating and alligatoring of a metal blank as it progresses through the rolling operation.

FIG. 2 is a perspective view illustrating schematically a metal blank being sheared in accordance with the present invention.

FIG. 2A is a side elevation view of the sheared end of the metal blank when sheared as shown in FIG. 2.

FIG. 3 is a side elevation view illustrating the shearing of a metal blank by an alternate form of shear blades.

FIG. 3A is a side elevation view of the metal blank after the shearing operation of FIG. 3.

FIG. 4 is a bottom plan view of a further alternate embodiment ofa shea'r'mgblade.

FIG. 4A is a top' plan view of a metal blank sheared in accordance with the shearing blade of FIG; 4.

FIG. 4B is a side elevation view of the metal blank of FIG. 4A.

FIG. 5 is a bottom plan view of another alternate embodiment of the shearing blade.

FIG. 5A is a top plan view of a metal blank sheared with the blade of FIG. 5.

FIG. 5B is a side elevation view of the metal blank of FIG.

FIG. 6 illustrates schematically the shearing operation at an intermediate location in the rolling process.

Referring now to FIG. I, there is illustrated schematically the various stages through which a metal blank, generally indicated by the reference numeral 10, passes-during a rolling process. Stage A shows the metal blank prior to rolling and the blank includes opposed top and bottom surfaces 12 and I4 transverse edge portion l5, 16. It should be noted that the edge portions l5, 16 are perpendicular to the opposed horizontal upper and lower surfaces 12 and 14.

The stages B through F illustrate the effect of the rolling operation on the metal blank as it is passed through a reversing rolling mill. Thus, stage B shows the blank after the initial rolling operations and it is to be noted that outer fibers of the blank comprising the top and bottom surfaces 12 and I4 have begun to be elongated while the inner portion of the blank has elongated to a lesser extent. The result is the formation of top and bottom crests l8 and 20 which are beginning to overlap the central portion 19 of the edge 16. The development of the crests 18 and 20 relative to the central portion 19 becomes more pronounced as the rolling process continues as is apparent in stage C and ultimately results in the elimination of the valley 19 as the crests l8 and 20 are further elongated and come together to form a lamination. It should be noted in stage D that the uneven elongation of the metal blank occurs even in the crest portion of the blank so that the extreme outer fibers of the crests l8 and 20'tend to elongate more than the inner fibers of the crest.

In stage E of the rolling operation, the laminating of the material has become more pronounced and defined top and bottom layers 22 and 24 have now been formed. These relatively thin top and bottom layers have a tendency to alligator or roll up at their leading edges 26 as is apparent in stage E. The alligatoring effect becomes more pronounced as the rolling process continues and thelayers 22 and 24 tend to separate at the extreme outer ends to form an opened mouth which renders itextremelydifficult to feed the blank into the next rolling station.

In view of the tendency to laminate and alligator, the metal blanks normally are sheared at intermediate stages in the rolling operation and also prior to entry into the tandem hot mill. Traditionally, this shearing of the metal blank has simply entailed removing the laminated portion of the blank to form a traverse edge which is perpendicular to the upper and lower surfaces of the blank. In other words, the shearing operation simply produces an end on the metal blank which is substantially the same as the blank had when it was first formed and further reduction of the blank after the shearing operation simply results in the formation of the same laminated end as previously described.

In accordance with this invention, it is contemplated that the shearing operation will be designed to minimize the subsequent tendency of the metal blank to laminate and alligator. This is accomplished by shearing the metal blank in a particular configuration using specially designed shear blades. Thus, referring to FIG. 2, opposed shear blades 30, 32 are provided with the shear blades having a length sufficient to extend across the width of the metal blank. Both shear blades are identical in the construction of their cutting faces. The cutting faces of the shear blades includes opposed beveled side faces or surfaces 33, 34 which converge to define a cutting edge 35. The surfaces 33, 34 define therebetween an included angle which is preferably in the range of 30 to 120. With each of the shear blades 30, 32 having an included angle within this range, the resultant cut of the metal blank produces an angle on the leading edge of the sheared blank which has an apex angle in the range of approximately 60 to l(). It is contemplated that the shearing blades 30, 32 will be restrained in their movement toward each other so that the two blades do not come into contact at the completion of the shearing operation. This separation of the shear blades 30, 32 results in a small flat section 36 which is defined by a line drawn between the cutting edges 35 of the two blades. The separation of the metal is ultimately accomplished by the wedging action of the blades 30, 32 since complete penetration of the meal is prevented.

FIG. 2A illustrates the leading edge of a freshly severed metal blank. This leading edge now includes beveled upper and lower leading edges 37, 38 terminating in the above described narrow flat section 36. With this arrangement, the feeding of the metal blank into the rolls of a mill is greatly facilitated. MOre importantly, however, the tapered leading edge surfaces 37, 38 provide for growth of the outer fibers of the upper and lower surfaces 12, 14 of the metal blank as the blank is passed through the rolling operation. Thus, as the outer fibers tend to elongate, the crest and valley configuration described above does not occur for a considerable period of time since the growth of the outer fibers along the surfaces 37, 38 merely tend to return the blank to a condition wherein the leading edge is perpendicular to the upper and lower surfaces. As a result, such lamination as occurs is compensated for and the tendency to alligator is significantly diminished.

Referring now to FIGS. 3 and 3A, there is illustrated an alternate form of a cutting blade. The cutting blades 40 are similar in configuration to the cutting blades of FIG. 2 in that they do employ opposed side faces 42, 43 which converge to a cutting edge 44. However, the side faces 42, 43 each have a double beveled configuration with a secondary beveled surface 42a and 43:: immediately adjacent the tip so that the included angle between the surfaces 420, 43a is larger than the included angle between the surfaces 42, 43. The use of a double bevel as shown in FIG. 3 provides relief for the shearing blades as they penetrate the work blank thereby reducing the amount of force required to shear the metal blank. FIG. 3A il lustrates the resultant sheared metal blank which has a correspondingly double beveled surface 46, 47 tapering to a cen- The blades 50 thus make the beveled cut of the metal blank along an angle extending across the metal blank as shown in FIG. 4A.

FIG. 5 shows a further embodiment modification which is similar to FIG. 4 in that the shear blade 60 may be made in two parts but, instead of an abrupt angle between the two pieces 60a, 60b of the shear blade, the blade is curved to provide the beveled cut on the metal blank across a gently curving line as shown in FIG. 5A. The blades 50 and 60 are similar to blades 30, 32 in that the side faces have a continuously beveled surface. It is to be understood that blades 50, 60 might also employ the double beveled configuration of blade 40 shown in FIG. 3.

The above-described shear blades may be employed in any type of press or other mechanical means whereby at least one of the shear blades is moved toward the other to cause penetration of the metal blank. Schematically illustrated in FIG. 6 is such an arrangement in which a plurality of rolls 70 are illustrated with the metal blank 10 passing through the rolls. The shearing apparatus comprises the shear blades 30, 32 with the shear blade 32 being fixedly supported in a frame 74. The upper shear blade 30 is mounted for reciprocation between guides 76 along a line coaxial with the shear blade 32. Some form of ram or platen 78 may be used to reciprocate the shear blade 30 with appropriate means to limit the movement of the shear blade 30 toward the shear blade 32. Any appropriate mechanism may be employed to accomplish this purpose, such as a stop mounted on the frame, or other limiting means which limit the movement of the ram 78. For purposes of illustration, a stop 80 has been shown on the guide mechanism 76.

It is to be appreciated that the arrangement shown in FIG. 6 is purely for purposes of illustration and is not to be construed as limiting since other arrangements for mounting and operating the shear blades are entirely possible. For example the shear blades may be operated without the necessity of guides 76 or both of the shear blades 30, 32 may be mounted for reciprocation. The essence of the arrangement is the particular configuration of the shear blades together with some provision for reciprocating at least one of the shear blades and means for limiting the amount of reciprocation to prevent contact between the two shear blades when the workpiece is severed.

I claim:

1. Apparatus for shearing hot rolled metal blanks to form particular beveled edges in order to minimize fiber elongation in said blanks during process rolling comprising:

a pair of diametrically opposed elongated shear blades, each having a length substantially coextensive with the width of said blades;

means for supporting said shear blades in said opposed relationship with at least one of said shear blades being movable toward and away from the other of said shear blades;

each of said shear blades having tapering side faces on opposite sides thereof converging to a cutting edge with the angle therebetween being in the range of from 30 to I20"; and

stop means for cooperating with said shear blades to prevent engagement of said cutting edges with each other.

2. The apparatus of claim 1 wherein said side faces on said shear blades each have a double beveled surface with the included angle between the beveled surfaces adjacent the cutting edge being greater than the included angle of the beveled surfaces remote from said cutting edge.

3. The apparatus of claim 1 wherein said shear blades have a V-shaped configuration in longitudinal section.

4. The apparatus of claim 1 wherein said shear blades have a curved configuration in longitudinal section. 

1. Apparatus for shearing hot rolled metal blanks to form particular beveled edges in order to minimize fiber elongation in said blanks during process rolling comprising: a pair of diametrically opposed elongated shear blades, each having a length substantially coextensive with the width of said blades; means for supporting said shear blades in said opposed relationship with at least one of said shear blades being movable toward and away from the other of said shear blades; each of said shear blades having tapering side faces on opposite sides thereof converging to a cutting edge with the angle therebetween being in the range of from 30 to 120*; and stop means for cooperating with said shear blades to prevent engagement of said cutting edges with each other.
 2. The apparatus of claim 1 wherein said side faces on said shear blades each have a double beveled surface with the included angle between the beveled surfaces adjacent the cutting edge being greater than the included angle of the beveled surfaces remote from said cutting edge.
 3. The apparatus of claim 1 wherein said shear blades have a V-shaped configuration in longitudinal section.
 4. The apparatus of claim 1 wherein said shear blades have a curved configuration in longitudinal section. 